JPH0423565B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an adsorption device for filtering contaminated air.
In particular, the present invention relates to a sealing structure when a sample container is removed for checking the deterioration state of an adsorbent used as an adsorption layer of an adsorption device.

(Prior Art) Nuclear power generation facilities are provided with an adsorption device 2 inside a casing 1 as shown in FIG. 3 in order to filter contaminated air.
A sample container 10 is provided as a means for checking the deterioration state of the adsorbent A.
is installed (Special Publication No. 55-35974).

This sample container 10 is removably attached to the shielding plate 6 of the contaminated air inflow path 3 at multiple locations parallel to the adsorption layer 4 and the inflow air flow via attachment pipes 7 that communicate with the contaminated air. The same adsorbent A as the adsorbent A filled in the adsorption layer 4 is filled inside the adsorption layer so as to have the same thickness as the adsorption layer 4 (FIG. 4).
Contaminated air is passed through the sample container 10 and discharged into the casing 1, passed through the adsorption layer 4, merged with filtered clean air, and released into the atmosphere.

In this device, it is confirmed that there is no bypass leak in the sealing structure of the adsorption layer 4 and O-rings 11 by flowing fluorocarbon gas when filling the adsorbent and after installing the adsorption device. In addition, when any one of the multiple locations is taken out for testing after operation for a predetermined period of time, the blind flange 30 is attached to the mounting pipe 7 to seal that location. To check for deterioration of seals such as No. 11, regularly conduct a bypass leak test using Freon gas.

On the other hand, the essential deterioration of the adsorbent A is determined from the analysis results of the adsorbent A periodically collected from the sample container 10, and the timing for replacing the adsorbent A filled in the adsorption layer 4 of the adsorption device 2 is determined.

Therefore, fluorocarbon leak tests and adsorbent sampling have different viewpoints and must be carried out separately and periodically. However, when the sample container 10 is removed,
Since we have not confirmed that there are no leaks in the part where the blind flange 30 is attached, be sure to conduct a fluorocarbon leak test after removing the sample container 10, and also perform a fluorocarbon leak test on the adsorption device 2.
This must be done for the entirety.

(Problems to be Solved by the Invention) As mentioned above, in the conventional apparatus, a fluorocarbon leak test must be performed every time the sample container 10 is removed, so a large amount of fluorocarbon gas is adsorbed to the adsorbent A. Breakthrough occurred from the downstream of layer 4, resulting in excessive fluorocarbon leak testing, and adsorbent A
There is a problem in that there are often cases where it is necessary to replace the parts.

(Means for Solving the Problems) Therefore, as a means for solving the above problems, the present invention provides an adsorption layer 4 that is filled with an adsorbent A and filters contaminated air passing therethrough, and a contaminated air inlet path 3. A plurality of sample containers 10 are installed alternately in the casing 1, and a sample container 10 is removably attached to the shielding plate 6 of the contaminated air inflow path 3 via an attachment pipe 7 that communicates with the contaminated air. In the adsorption device 2 filled with the same adsorbent A as the adsorbent A filled in the layer 4, there is provided a first flange 16 that airtightly seals the inside of the attachment pipe 7, and a predetermined gap between the first flange 16 and the adsorbent A. A second flange 19 is formed to airtightly seal the outside of the first flange 16, and a leak test port 20 is provided on the second flange 19, so that both flanges 16 and 19 can be attached to and detached from the mounting pipe 7. That is.

(Function) The present invention provides the following effects by the above means. That is, according to the present invention, the seal is ensured by the double seal structure with the double inner and outer flanges, and the seal can be confirmed by checking the leak test port 20 provided on the second flange 19 between the first flange 16 and the second flange. Space B formed between 19
Since the double seal structure alone can be used to confirm leakage by injecting fluorocarbon gas and measuring gas leakage using a halide detector, there is no need to perform a leak test on the entire adsorption device 2 after taking out the sample container 10. It's good.

(Embodiment) An adsorption device as a preferred embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 3. Reference numeral 1 is a casing that forms an air flow path for discharging contaminated air containing radioactive materials in a nuclear power generation facility, and 2 is an adsorption device that is installed within the casing 1 and filters the contaminated air. The adsorption device 2 has a plurality of contaminated air inflow paths 3 that open in an upstream shielding plate 5 that is perpendicular to the inflow air path of the casing 1 and into which contaminated air flows, and activated carbon, etc., that filter the contaminated air to make clean air. A plurality of adsorption layers 4 filled with granular adsorbent A and formed parallel to the incoming air flow.
... are arranged alternately in an appropriate number, and the incoming contaminated air is passed through the adsorption layer 4 and filtered by the adsorbent A filled in the adsorption layer 4, and the filtered clean air is passed through the opening of the shielding plate 6. When the adsorption capacity of the adsorbent A deteriorates due to the adsorption capacity of the adsorbent A being discharged into the casing 1, the deteriorated adsorbent A is discharged from the adsorption layer 4, and the adsorption layer 4 is refilled with new adsorption agent A.

The deterioration of the adsorption capacity of the adsorption device 2 is determined as follows. That is, one end of a plurality of mounting pipes 7, each curved at 90°, is protruded and opened from a shielding plate 6 at the end of a plurality of contaminated air inflow channels 3 provided in the casing 1 to form an inflow port 8, and the other end is opened. A sample container 10 is attached to each outlet port 9 that opens downward at the end. Each sample container 10 is divided into three cylindrical members 10a. The cylindrical member 10a has a cylindrical shape with the top and bottom open.
The same adsorbent A was used as the adsorbent A filled in the . The three divided cylindrical members 10a are hermetically polymerized via an O-ring 11, and the polymer is hermetically connected between the upper connecting pipe 12 and the lower connecting pipe 13 by bolts 14, 14... Furthermore, this combined body is attached to each mounting tube 7 via an O-ring 11 with bolts 14, 14, . . . in an airtight manner. Note that the total thickness of the adsorbent A divided into three parts of the sample container 10 is approximately equal to the thickness of the adsorbent A of the adsorption layer 4.

Therefore, in order to periodically test the deterioration state of the adsorption layer 4, any sample container 10 among the plurality of sample containers 10 provided is removed from the mounting tube 7. A flat first flange 16 for airtight sealing is loosely fitted into the inner diameter of the outlet port 9 through an O-ring 26 housed in an annular groove 25 formed in the inner diameter, and a plurality of concentric bolts 14 are connected to the outlet port 9 of the outlet 9. Tighten, and then tighten the first
A flat second flange 19 located outside the flange 16 is provided, and the outer diameter formed on the annular projection 17 of the mounting pipe 7 and the second flange 19 are connected to the second flange 1.
The mounting tube 7 is tightened airtightly with a large number of concentric bolts 14 via an O-ring 28 housed in an annular groove 27 formed in the inner diameter of the tip of the annular projection 18 of 9.

Therefore, a space B of the minimum size necessary for the leak test is provided between the first flange 16 and the second flange 19 having the double seal structure. In addition, a leak test port 20 is bored in the second flange 19, and the leak test port 20 is provided in the second flange 19.
An on-off valve 22 is interposed in the piping 21 which is airtightly connected to the 0, and is further connected to a gas cylinder 24 filled with fluorocarbon gas through a connecting pipe 23.

To perform a leak test using the above device, first open the on-off valve 22, inject Freon from the gas cylinder 24 into the space B between the flanges 16 and 19, close the on-off valve 22, and use a halide detector (not shown). Detects whether there is any gas leakage from parts such as O-ring 28, and double-sealed structure alone.
A leak test is performed independently of the entire adsorption device 2.

In addition to the above-mentioned halide detector, the leak test may also be carried out by injecting gaseous fluorocarbon gas, compressed nitrogen, compressed air, etc. into the space, and measuring with a pressure gauge if there is no change in pressure after a certain period of time has elapsed. It is.

Further, in the above embodiment, the first flange 1
6 is an annular groove 25 formed on the inner diameter of the mounting pipe 7 and O
Through the ring 26, the second flange 19 is connected to the annular groove 27 formed on the inner diameter of the annular projection 18 of the flange 19 and the outer diameter of the annular projection 17 of the mounting tube 7.
Although the rings 28 are used to seal each other, the present invention is not limited to the embodiment described above.
has a predetermined gap with the first flange 16, and the first
Any material that airtightly seals the outside of the flange 16 may be used.

(Effects of the Invention) As described above, the adsorption device of the present invention has a reliable blind structure with an independent double seal structure, and allows a leak test to be performed by flowing a test gas through the entire adsorption device 2 after the sample container 10 is removed. It is not necessary, so
The number of freon gas leak tests can be reduced, performance deterioration of the adsorbent A due to leak tests can be prevented, and the life of the adsorbent A can be extended.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing a double seal structure for a mounting tube to which a sample container is attached as an embodiment of the present invention, and Fig. 2 is a longitudinal cross-sectional view showing a state in which a sample container is attached according to an embodiment of the present invention. Figure 3 is a partially cutaway perspective view of a general adsorption device, Figure 4 is a vertical sectional view showing the sample container of the conventional device attached, and Figure 5 is also a seal structure of the conventional device. FIG. DESCRIPTION OF SYMBOLS 1... Casing, 2... Adsorption device, 3... Contaminated air inflow path, 4... Adsorption layer, 6... Shielding plate, 7
...Mounting pipe, 10...Sample container, 16...First flange, 19...Second flange, 20...Leak test port, A...Adsorbent, B...Space.

Claims (1)

[Claims] 1. A plurality of adsorption layers 4 filled with adsorbent A and filtering the contaminated air passing therethrough and a plurality of contaminated air inflow paths 3 are installed alternately in the casing 1, and the shielding plate 6 of the contaminated air inflow path 3 is provided with the contaminated air and the contaminated air. In the adsorption apparatus 2, a sample container 10 is removably attached via a communicating attachment tube 7, and the sample container 10 is filled with the same adsorbent A as the adsorbent A filled in the adsorption layer 4. The first to airtightly seal the inside of 7.
Between the flange 16 and the first flange 16
and a second flange 19 that airtightly seals the outside of the first flange 16, and a leak test port 20 is provided on the second flange 19, and both flanges 16, 19 are connected to the mounting pipe 7.
A suction device characterized in that it can be attached to and detached from.